This invention relates to a ventilation apparatus and more particularly to a power vent for ventilating an attic space or the like.
Various forms of ventilation systems have been proposed for removing warm air from an attic space or the like during warm weather to reduce air conditioning loads. These systems are also used to remove insulation damaging moisture from the ventilated spaced during the winter months. Prior proposals have taken the form of either a natural ventilation system or a power ventilation system. With either system, a plurality of under eaves vents are provided. Natural systems include hooded roof vents mounted in apertures formed in the roof or a continuous, roof ridge vent mounted at the ridge or peak of the roof.
In order to increase the amount of air removed from such spaces, to supplement existing systems, to further decrease air conditioning loads or to ventilate other areas which may contain noxious fumes, power ventilators or power vents are employed. These vents are either mounted on the roof adjacent the peak or roof ridge of the roof at apertures formed therein or are mounted at the gable end of the roof structure. Typically, either of these two types of power vents include some form of mounting flange or base and a tubular shroud or duct within which is disposed a fan assembly. The duct is mounted at either an opening in the roof or at the gable end of the roof behind a louver assembly.
Various attempts have been made to develop power vents which are sufficiently durable to withstand exposure to the elements including wind, rain, snow, heat, cold and sunlight yet still be capable of moving sufficient air from the ventilated space and with minimum noise. Reliability is a critical factor since these structures are mounted in relatively inaccessible or hard to reach areas such as on the roof of the home or building or within an attic space.
Examples of some prior ventilators of the general type under consideration may be found in U.S. Pat. Nos. 2,926,837, entitled POWER ROOF VENTILATOR and issued Mar. 1, 1960 to Robert D. Coe; 2,987,983, entitled PLASTIC CASING FOR AIR EXHAUSTER and issued June 13, 1961 to I. I. Solzman; 3,302,551, entitled VENTILATOR and issued Feb. 7, 1967 to P. D. Van Belle; and 3,934,494, entitled POWER VENTILATOR and issued Jan. 27, 1976 to Henry N. Butler.
The aforementioned U.S. Pat. No. 3,934,494 discloses a power ventilator which is fabricated from a plastic material such as polyethylene. The ventilator includes a housing assembly which is heat-shrunk onto a wire frame assembly. The wire frame is provided to reinforce the polyethylene material. Another fairly complex multi-piece frame assembly is employed to support a hood above the housing assembly and to secure the housing assembly to the roof of a building. Further, the motor of the fan assembly includes flanges to secure the motor to a plurality of motor mount brackets defined by the hood support frame assembly.